Unionized nurses at Liberty Dialysis Hawaii have ratified a new three-year labor agreement that includes a 6 percent wage increase over life of the contract.

The contract, negotiated on behalf of the nurses by the Hawaii Nurses Association, also calls for:— Differential pay of $1.50 per hour for “preceptor” nurses, experienced nurses who mentor and train new nurses;—Differential pay of 50 cents per hour for nurses who have a nephrology certification. Such nurses specialize in renal dysfunction;— Differential of $150 a week for nurses who consult with patients at home over the phone.Liberty Dialysis, based in Washington state, has more than a dozen clinics on O'ahu, Kaua'i, Maui, Moloka'i and the Big Island.